1. Field of the Invention
The present invention relates to a pressure plate assembly for a friction clutch including a housing arrangement designed to be connected to a centrifugal mass arrangement; a pressure plate mounted in the housing arrangement with freedom to move in a direction parallel to an axis of rotation; a stored-energy device; and a wear take-up device acting in the path of force transmission between the stored-energy device and the pressure plate, where the wear take-up device has at least one take-up element which can be moved in a take-up direction to compensate for wear. A play sensor arrangement includes a detection element on the pressure plate, which element, upon the occurrence of wear, makes contact or can be brought into contact with a blocking element, which is in a fixed position with respect to the housing arrangement. The blocking element has a fastening area by which it is held in place with respect to the housing arrangement and a contact area by which it makes contact with the detection element.
2. Description of the Related Art
A pressure plate assembly of this type is known, for example, from U.S. Pat. No. 6,123,180. In an embodiment of this known pressure plate assembly, a plate-like blocking element, which is stamped, for example, from a metal plate is fastened by a threaded bolt to the outer circumferential area of the housing arrangement and projects from there radially inward so that it can work together by contact with the detection element. Because of its elongated shape, the blocking element is subject to comparatively severe bending loads when it contacts the detection element, which means that its flexure can cause a lack of precision in its interaction with the detection element and, thus, to this extent can cause a lack of precision in the wear take-up process to be performed in response to this interaction.
The object of the present invention is to make sure that the wear in a pressure plate assembly of this type can be detected with a high degree of precision.